Recent developments in 3GPP Long Term Evolution (LTE) facilitate accessing local IP-based services in the home, offices, public hot spots or even outdoor environments. One of the important use cases for the local IP access and local connectivity involves the direct communication between devices in the close proximity (often referred to as “D2D” communication, typically less than a few tens of meters, but sometimes up to a few hundred meters) of each other.
In most cases, the D2D transmission can reuse cellular uplink (UL) resources. To implement this direct D2D communication in a traditional cellular network, it is important to get knowledge of the interference channel between the cellular UE transmitter and D2D UE receiver to avoid strong intra-cell interference, i.e., interference from cellular UL transmission to D2D link within the cell.
To get information about this interference channel from cellular UE transmitter to D2D UE receiver, the prior arts proposed some approaches by enabling D2D UEs to monitor the received interference from UL transmission by cellular UEs. However, existing interference measurement schemes have not proposed a solution in the multi-cell and multi-antenna scenario. For example, in a multi-cell scenario, the interference could not be measured in a UE-specific way (i.e., for each cellular UE respectively). As another example, for cellular UEs equipped with multiple Transmission antennas (e.g., standardized in 3GPP Rel-9, 10), the power measurement could not distinguish the amplitude and phase information from different antennas, i.e., the interference could not be measured in an antenna-specific way.
Thus, the existing interference channel measurement schemes are desired to be improved to obtain the interference channel information required in a practical network, for example, LTE network, to address those problems.